Analysis on the Climate Change Characteristics in the Shihezi Region,Xinjiang in Recent 40 Years

The Shihezi region(43°26′～45°20′N,84°58′～86°24′E,300～500 m a.s.l.) is located in the middle section of northern piedmont of the Tianshan Mountains and the southern marginal zone of the Gurbantonggut Desert in Xinjiang,and its total area is 7 529 km~2.In the region it belongs to the typical temperate continental arid climate,winter is cold and long but summer is hot and short,and the annual temperature,sunshine duration,frost-free period,precipitation and evaporation vary in ranges of 7.5～8.2 ℃,2 318～2 732 hours,147～191 days,180～270 mm and 1 000～1 500 mm respectively.Irrigated agriculture is dominant in the Shihezi region.Therefore,it is of significance for agricultural development to research the change characteristics of air temperature,precipitation,sunshine duration,etc.In this paper,the change characteristics of air temperature,precipitation,sunshine duration in the Shihezi region since recent 40 years are analyzed based on the meteorological data observed during the period of 1961-2001.The results show that the annual,winter and summer temperatures are generally in an increase trend,they were decreased or stable during the period from the 1960s to the 1970s but increased during the period from the 1980s to the 1990s,the temperature increase was more significant in winter than that in summer in the 1980s,but it was more significant in summer than that in winter in the 1990s;precipitation is generally in an increase trend,its increase rate is 10.6 mm pre decade,and the annual precipitation in the 1990s was increased by 20.8% than the 30-year average;the annual sunshine duration is generally in a decrease trend but not so significant,and its decrease rate is-9.2 hours per decade.The climate in the Shihezi region is trending from warming-drying pattern to warming-wetting pattern,which is advantageous for agricultural development.